Description

The getnetbyaddr(), getnetbyname() and getnetent(), functions each return a pointer to a
netent structure, the members of which contain the fields of an entry
in the network database.

The getnetent() function reads the next entry of the database, opening a
connection to the database if necessary.

The getnetbyaddr() function searches the database from the beginning, and finds the
first entry for which the address family specified by type matches the
n_addrtype member and the network number net matches the n_net member, opening
a connection to the database if necessary. The net argument is the
network number in host byte order.

The getnetbyname() function searches the database from the beginning and finds the
first entry for which the network name specified by name matches the
n_name member, opening a connection to the database if necessary.

The setnetent() function opens and rewinds the database. If the stayopen
argument is non-zero, the connection to the net database will not be
closed after each call to getnetent() (either directly, or indirectly through one
of the other getnet*( ) functions).

The endnetent() function closes the database.

Usage

The getnetbyaddr(), getnetbyname() and getnetent(), functions may return pointers to static data,
which may be overwritten by subsequent calls to any of these functions.

These functions are generally used with the Internet address family.

Return Values

On successful completion, getnetbyaddr(), getnetbyname() and getnetent(), return a pointer to a
netent structure if the requested entry was found, and a null pointer
if the end of the database was reached or the requested entry was
not found. Otherwise, a null pointer is returned.